Human growth hormone, also known as somatotropin, is an anterior pituitary hormone comprised of 191 amino acids and has a molecular weight of 22,000 daltons. It can be isolated from human pituitary glands or can be prepared biosynthetically as a result of advances in genetic engineering. At present there are two commercially available forms of the genetically engineered hormone, one of which is identical to native human growth hormone. The other form has an additional methionine residue at the N-terminus of the protein.
Human growth hormone is administered parenterally. A difficulty which has been encountered in the preparation of the pharmaceutical parenteral product has been that of aggregation of the human growth hormone upon storage. The present invention obviates this problem by providing parenteral formulations which are stabilized against aggregation of the human growth hormone.